user demand has demonstrated a need for increasingly higher speed digital access in new office communication controllers as daily routines become more complex and greater demands are placed on improving productivity. Current Local Area Network (LAN) solutions that provide this higher speed are beset by high cost and congestion. Moreover, these solutions are usually poorly suited to integrating voice services.
An alternative to the tradiational LAN approach is to integrate all voice and data services into a centralized controller and to utilize inexpensive standard in-building twisted pair wiring to provide the required interconnects. A commonly experienced problem in this approach is the restriction to low baud rates for transmission. Notwithstanding the limited transmission capability of standard twisted pair wiring, a viable centralized controller is expected to execute both ends of a 2.56 Mb/s digital line interface over such wiring.